1. Field of the Invention
The invention relates to mobile devices with multiprocessor, and in particular, to a method for reducing power consumption during data connection.
2. Description of the Related Art
For public internet services via wireless access, traffic directed to a user equipment (UE) is not always meant for the UE. Such traffic can be from unknown sources trying to probe the UE TCP open ports to gain unauthorized accesses to the UE. According to the Transmission Control Protocol/Internet Protocol (TCP/IP) standard, when a sender side tries to open sockets to a targeted UE, the sender side will send a TCP [SYN] packet to determine whether the target UE's TCP port is open. If the UE's TCP port is not in a listening state or in other words there is no service running on that particular port, the UE will send an RST ACK response back to the sender. For conventional operations such as Telnet, the sender will retry twice before finally giving up and determining a failed connection. Meanwhile, unwanted traffic, also known as garbage traffic, causes problems, particularly in 3rd Generation Partnership Project (3GPP), 3.5G or 2G data connections. When the UE activates a Packet Data Protocol (PDP) context in the 3G or 2G Network to obtain a public IP address for data connection, the UE is exposed to the internet unprotected, and consequently may be overwhelmed by garbage traffic.
Processing the garbage traffic takes a significant amount of power consumption. The negative effect is most noticeable for mobile devices with limited battery life. Therefore, a method for reducing power consumption during data connection is desired.